The invention relates to a medical device particularly for use in surgery to provide surgical access to the abdomen and maintain a gas-tight seal around the arm or an instrument during surgery. Surgery of this type is referred to as hand-assisted laparoscopic surgery or hand-access surgery.
Conventional abdominal surgery requires the creation of an incision in the abdominal wall to allow access to, and visualization of the internal organs and other anatomical structures. These incisions must be large enough to accommodate the surgeons hands and any instruments to be utilised by the surgeon during the surgery. Traditionally the size of these incisions has been dictated by the need to see, retract and palpate internal bodily structures. While a large incision will provide access to the interior of the abdomen they are associated with longer healing times, are more susceptible to infection and result in unsightly scars.
Alternatives to open surgery exist in the form of endoscopic or laparoscopic surgery. In this method of surgery, the surgeon operates through small incisions using remotely actuated instruments. The instruments pass through the abdominal wall using devices called trocars. These working channels typically have a diameter ranging from 5 to 25 milimeters. Vision is provided using a laparoscope which is typically 20 to 25 centimeters long and uses fiber-optic technology or a CCD camera to provide the operator with a picture of the interior of the abdomen. The abdomen must be insufflated with a gas such as carbon dioxide or nitrogen to maintain a bubble effect and provide a viable working space for the operator to perform the surgery unhindered by the lack of space. This insufflation creates a working space known as the pneumoperitoneum. Trocars through which instruments are inserted are constructed to prevent loss of the gas through them resulting in collapse of the pneumoperitoneum.
The benefits of laparoscopic surgery are numerous. Recovery times have been shown to be reduced due to the absence of a large incision. This has benefits for the patient, the health care organisation and society. The benefits to the patient are reduced stay in hospital, faster mobilisation and return to normal activity. The benefits to the health care organisation is also due to the reduced stay in hospital which is often the most expensive aspect of health care provision. Society benefits in faster return to work and normal activity of the patient.
However, not all surgical procedures can be performed laparoscopically. Surgery requiring the removal of large organ specimens, such as surgery for removal of the colon, has traditionally been hampered by the small incisions used for the introduction of laparoscopic instruments in the surgery.
The other major disadvantages of laparoscopic surgery are due to the complex nature of the technique. Surgeons who wish to practise laparoscopic surgery must spend much time training to master the technique. The success of laparoscopic surgery depends on the skill of the surgeon to manipulate organs and carry out delicate tasks using remotely actuated instruments. Unfortunately in laparoscopic surgery the surgeon is insulated from the material that they are working on. This deprives the surgeon of tactile feedback and the ability to palpate delicate structures. The surgeon""s most effective instrument, the hand, is reduced to a device that must simply actuate instruments that are inherently lacking in dexterity and operability due to the constraints on their design placed by the nature of the narrow channels in trocars through which they must pass. Another disadvantage of laparoscopy is that the image viewed by the surgeon is a two dimensional image on a video screen. The surgeon loses three dimensional perspective of depth and distance and awareness of the proximity of other structures during video laparoscopy.
These disadvantages have led to long learning curves for the practitioners of laparoscopic surgery, required highly skilled and coordinated surgical teams and has limited the application of laparoscopic surgery to relatively simple surgical procedures.
Recently, new surgical techniques have been developed that combine the advantages of both open surgery and laparoscopic surgery. In these new techniques surgery is carried out using a laparoscopic approach with the addition of a slightly larger incision to allow the surgeon to insert a hand into the insufflated abdomen. This is often referred to as hand-assisted laparoscopic surgery or HALS.
HALS allows surgeons to regain the tactile feedback and three-dimensional perspective lost in the conversion from open to laparoscopic procedures. It also permits rapid finger dissection, enhanced retraction capabilities and simplified haemostasis. There are several publications in the literature describing procedures carried out using a hand-assisted approach. These include total and sub-total colectomy, rectopexy, Nissen""s fundoplication, gastrectomy, splenectomy, nephrectomy, pancreatectomy and others. Some of these procedures were previously performed using an open technique only. Over the past few years several centres have been investigating HALS with surgical device companies and increasing the literature on the subject. With the advent of surgical devices for facilitating HALS it is expected that more open surgical procedures will be converted to HALS procedures.
The key to the success of hand-assisted laproscopic surgery will be to provide a device that will seal to the wound edge and to a surgeons arm to maintain the pneumoperitoneum required. The device should provide freedom of movement including rotational, lateral and translational. In addition, it should be possible to use laparoscopic instruments with the device.
Various hand access devices have been proposed however, to date, no hand access device is available that adequately addresses these key issues.
U.S. Pat. No. 5,366,478 (Brinkerhoff et al) describes a device which is said to be for use during endoscopic surgery. The device has two inflatable toroidal sections connected by a transitional section. The transitional section is said to function to allow the passage of air from one toroid to the other toroid on inflation of the device. Each toroidal section contains a flexible stiffening ring. The stiffening ring in the outer toroid is illustrated in a position floating above the abdominal wall after inflation. It is not clear how this device provides a seal however in any event it would be difficult to pass an object such as a surgeon""s forearm through a lumen in the transitional section, because of frictional resistance to the movement of the object relative to the transitional section.
A medical device for forming an external extension of the pneumoperitoneum is described in U.S. Pat. No. 5,480,410 (Cuschieri et al). The device includes an enclosure sealed into a trocar puncture site in an abdominal wall. Insuffiation gas passes from the body cavity into the enclosure inflating it A number of valved openings are provided on the device to enable access to the enclosure interior.
In U.S. Pat. No. 5,514,133 (Golub et al) describes an endoscopic surgical apparatus, to enable a surgeon to access a surgical site through an opening. The apparatus includes two plates, which engage the outer and inner surfaces of the abdominal wall, and a sealing member, which inhibits the flow of gas through the opening. It is expected that the seal in this apparatus would not maintain complete insufflation of the body cavity as gas can gradually leak out through the flapvalves and seal. The valve configuracion also makes it impossible to extracorporealise an organ, which is preferred in hand-assted surgery devices. The device also has a complicated construction.
A surgical glove suitable for use in endoscopic surgical procedures is described in U.S. Pat. No. 5,526,536 (Cartmill). The glove has an inflatable wrist section, which when inflated, is said to provide a seal between the surgeon""s hand and the body wall. The surgeon""s gloved hand must remain in the body cavity to maintain insufflation of the body cavity. Therefore this device also restricts the actions of the surgeon.
U.S. Pat. No. 5,522,791 (Leyva), describes an abdominal retractor, which retracts an abdominal incision providing access for a hand into a body cavity. The hand is passed into a sleeve and the other end of the sleeve is mounted to the retractor.
U.S. Pat. No. 5,545,179 (Williamson) describes an access assembly, which provides access for surgical instruments to a body cavity during surgery. A sealing sleeve is inflated to form a large balloon portion with the body cavity, the balloon portion being constrained to remain within the body cavity. It is difficult to retract a surgical instrument through a balloon portion and out of the body cavity, because of frictional resistance to the movement of the surgical instrument relative to the balloon sleeve.
A method of performing laparoscopic surgery is described in U.S. Pat. No. 5,636,645 (Ou), which includes the steps of inserting a surgeon""s gloved hand into a body cavity and sealing the hand to body tissue surrounding the cavity. This method restricts the actions of the surgeon because the surgeon""s gloved hand must remain in the body cavity sealed to the surrounding tissue to maintain insufflation of the body cavity. The seal between the surgeon""s gloved hand and the surrounding tissue must be re-established each time the gloved hand is inserted into the body cavity, if insufflation of the body cavity is to be maintained.
An apparatus and a method for carrying out minimally invasive laparoscopic surgery is also described in U.S. Pat. No. 5,640,977 (Leahy et al). A surgeon""s hand is passed through a sleeve to access a body cavity, the sleeve being sealed around the surgeon""s forearm.
U.S. Pat. No. 5,653,705 (de la Torre et al) discloses an envelope, which is said to provide access for an object passing into a body tissue incision, while maintaining insufflation of the body cavity. A first opening in the envelope is sealed around the body tissue incision and a second opening is sealed around an object passed into the envelope.
Devices for use during surgery which provide access to a surgical site and effect a seal independent of a surgeon""s hand are also known. In general devices of this type are positioned predominantly external to a body cavity, and are complex, large and bulky. These devices prove difficult to use because they are cumbersome and/or because of their complexity. For example, a flexible, fluid-tight envelope to provide access for an object passing through a body tissue incision while maintaining insufflation pressure is described in U.S. Pat. No. 5,672,168 (de la Torre et al). This is a complex device including a first opening secured and sealed to the body tissue incision, and a second opening distal from the body tissue incision and sealed to a surgeon""s forearm. The device also includes a housing containing a valve element at the body tissue incision.
An access port device for use during a surgical procedure is described in U.S. Pat. No. 5,803,921 (Bonadio). An object is passed into the device sleeve, the device is sealed around the object at the sleeve opening and the device is also sealed at the body cavity.
U.S. Pat. No. 5,741,298 (MacLeod) describes a method for performing surgery using a multi-functional access port. The access port has a sealing ring which protects the body wall incision from contamination. A sealing cap or a surgical glove is connected to the sealing ring to maintain insufflation of the body cavity. This surgical method is also restrictive because the surgeon""s gloved hand must remain sealed to the sealing ring, if body cavity insufflation is to be maintained.
A surgical apparatus for use during hand assisted minimally invasive surgery is described in U.S. Pat. No. 5,813,409 (Leahy et al). A sleeve is mounted at one end to a body tissue incision. The sleeve seals to the surgeon""s hand to maintain pneumpperitoneum. Surgical instruments may then be passed into the sleeve to a surgeon""s hand within, which may then be inserted into the incision. This device is relatively large, requires a multistep process for installation and comes in several parts.
U.S. Pat. No. 5,906,577 (Beane et al) describes a retractor device for retracting the edges of an incision to form an opening to a body cavity. A flexible sleeve is mounted to the retractor, and an object passed through the device is sealed to maintain insufflation of the body cavity. This device also consists of many component parts that must be assembled carefully.
WO 98/35615 (Crook) describes a device for performing HALS that consists of a wound-edge retractor to which is attached a sleeve similar to others mentioned above. This device also consists of several component parts and has a complicated installation procedure.
An access port device for use during hand-assisted laparoscopic surgery is described in SP 10-108868 (Tamai, Shitomura). This device consists of a wound retractor component to which is attached an iris valve. The wound retractor component is made of two rings, an inner ring and an outer ring joined by a silastic sleeve to provide a retractive force. The device is inserted into an incision and the surgeon""s hand is inserted through the device. The iris valve is then closed around the arm to effect a seal to prevent the escape of insufflation gas.
Generally known devices are difficult to use because they are cumbersome and/or because of their complexity. In addition, tight seals are often not maintained and/or the movement of a surgeons arm is restricted and/or the device may become dislodged from a wound.
There is therefore a need for a sealing device, which provides effective sealing means to seal an object passing through the device, and which is convenient and easy to use, compact and neat, and may be used repetitively with minimum delay and minimum effort.
According to the invention there is provided a medical device comprising:
a sleeve of defining a lumen;
the sleeve having a twisted sleeve section defining a reduced lumen section; and
tensioning means to facilitate axial extension of the twisted sleeve section.
In a particularly preferred embodiment the sleeve is twisted to provide the twisted sleeve section. Most preferably the sleeve is of pliable material.
In a preferred embodiment the means to facilitate axial extension of the twisted sleeve section comprises a chamber for a pressuring fluid.
In this case the chamber may be defined by an outer sleeve section and an inner sleeve section.
Preferably the outer sleeve section is a substantially cylindrical sleeve section and the inner sleeve section is a twisted sleeve section of the same untwisted diameter as that of the outer sleeve section.
In a particularly preferred embodiment the sleeve is turned axially back on itself to define the outer sleeve section and the inner sleeve section.
Preferably the reduced lumen section is of a smaller size than that of an object to be received therein or passed therethrough.
In a particularly preferred embodiment on engagement of an object in the reduced lumen section and axial movement of the object relative thereto, the sleeve everts so that the twisted inner sleeve section is rolled over outwardly to become an untwisted outer sleeve section and the outer sleeve section is correspondingly rolled over inwardly to become a twisted inner sleeve section.
Preferably the chamber is fluid impermeable. Ideally the chamber is inflatable.
Preferably the chamber has an access port for inflation of the chamber.
In one particularly preferred embodiment the device includes eversion limiting means to axially limit eversion of the sleeve.
The device may have a first eversion limiting means for location externally of the opening and a second eversion limiting means for location internally of the opening.
Preferably the or each eversion limiting mean is an O-ring, preferably of a resilient material.
In one arrangement the or each eversion limiting means is housed in the chamber.
The or each eversion limiting means may be movable axially in the chamber.
In another arrangement there are two eversion limiting means and both are independently movable in the chamber.
In a further arrangement there are two eversion limiting means and a linkage means is provided between them. The linkage means may be of pliable material. Typically the linkage means comprises a linkage sleeve.
In another embodiment the eversion limiting means comprises first and second eversion limiting means attached at different locations to the sleeve.
Preferably the first eversion limiting means is attached to one end of the sleeve and the second eversion limiting means is attached at another end of the sleeve.
In a particularly preferred embodiment the eversion limiting means are movable relative to one another for twisting the sleeve. The eversion limiting means may be rotatable-relative to one another for twisting the sleeve.
In one embodiment the device includes handle means to facilitate movement of the eversion limiting means relative to one another.
Preferably the device includes locking means for locking the first eversion limiting means relative to the second eversion limiting means.
In another embodiment of the invention the tensioning means is a mechanical tensioning means.
In this case the tensioning means may comprise a spring means.
Preferably the reduced lumen section is sized to sealing engage an object passing therethrough.
In one aspect the device is for use in surgery.
The device may be a forearm seal for use in carrying out hand assisted laproscopic surgery.
Alternatively the device is an endoluminal device.
The device may be an introducer for introducing an instrument into a body through an opening.
The device may also be an exsanguinator or an envaginator.
In another aspect the device is a tissue dissector.
Alternatively the device is a trocar seal.